Steps to produce:
---
- Install website_sale module without demo.
- Create a new product and publish it.
- From the incognito, go to shop and add that product to cart.
- While doing checkout > fill the address form.
- Add the all details including the company name and valid VAT.
  (ex. BE0477472701)
- Submit the form.

Issue:
---
- When a public or guest user submits a new address with both a contact name
  and a company name along with a valid VAT number, the contact's name was
  being overwritten with the company name.

Root cause:
---
- The _compute_is_company heuristic in res.partner automatically sets
  is_company=True for partners with valid VAT. In [commit]
  `_create_or_update_address`, the condition `elif partner_sudo.is_company:`
  was designed to rename existing companies, but incorrectly caught newly
  created individuals marked as companies due to VAT, causing their name to be
  overwritten instead of creating a parent company.

Solution:
---
- Replaced the is_company check with explicit conditions: the partner
  has no parent_id, has contact-type child_ids.
- This ensures the rename-company branch only fires for actual company
  heads that the logged-in user belongs to, not for individuals that
  happen to have is_company=True due to a valid VAT.

[commit]: https://github.com/odoo/odoo/commit/8f3a32170c842f5f42edc79bf8620276f0da7be4

opw-6356772
---
I confirm I have signed the CLA and read the PR guidelines at www.odoo.com/submit-pr

When a helpdesk team has its website form enabled, a dedicated qweb view is generated from the `ticket_submit_form` template. The arch was read in the language of the user creating or editing the team, so a team set up by an English user language produced an English form even when the website served another language.

Steps to reproduce
==================
1. Set a language other than English as the website default language.
2. While your user language is English, create a helpdesk team with the website form enabled.
3. Open the team form on the website.

=> The form is rendered in English instead of the website language.

Root cause
==========
`_ensure_submit_form_view` read the template arch without forcing a language, so it used the current user's language and stored only that value on the generated per-team view.

Fix
===
Read the template arch in the default language of the team's website, so the generated form matches the website language regardless of the user's own language.

opw-6303903

Forward-Port-Of: odoo/enterprise#129265
Forward-Port-Of: odoo/enterprise#121164